This invention relates to the field of safety closures for containers, in which the closure includes a mechanism or structure that makes opening difficult enough that small children in particular cannot normally open containers having materials that would be harmful or dangerous, or that they should otherwise not be able to open.
A variety of such closure caps are known to the prior art which attempt to solve the problem in different ways, and a number of U.S. patents have been issued for such prior art closure caps including the following: U.S. Pat. Nos.
4,625,898, 4,377,247, 4,282,991, 4,220,248, 4,219,138, 4,209,114, 4,172,540, 4,124,151, 4,081,113, 4,047,643, 3,977,557, 3,967,764, 3,957,181, 3,893,593, 3,884,394, 3,881,643, 3,877,598, 3,874,568, 4,209,100, 3,873,005, 3,863,818, 3,860,137, 3,851,805, 3,784,060, 3,777,936, 3,774,808, 3,718,238, 3,655,103, 3,848,780, 3,844,455, 3,765,578, 4,635,823, 4,298,129, 4,281,778, 3,927,805, 4,298,129, 3,826,394, 4,220,262.
The safety closure cap in accordance with this invention provides a novel structure to achieve the safety objective. An outer continuous peripheral wall or skirt of the safety cap is spaced radially outwardly from an inner concentric peripheral wall which seats in the neck of the container to seal it closed. The continuous outer wall is integrally formed with the top closure wall of the cap and depends therefrom giving structural stability and strength to a deflectable barrier strip integrally formed therein which bars access to a hinged closure tab provided on the top closure wall until the barrier strip is deflected inwardly. A thin laterally extending web or nib extends upwardly from the outer portion of the upper edge of the deflectable barrier strip to cover the crack between the free end of the closure tab resting on and abutting against the upper edge of the deflectable barrier strip. Thus, a child for example cannot get his fingernail, or a knife, or other thin item into this crack to pry up the free end of the closure tab. The only way to gain access to an underportion of the closure tab to push it upwardly to the open position is by first pushing in on the deflectable barrier strip to expose an underportion of the closure tab. The closure tab has an elongated cylindrical plug extending downwardly from its inwardly facing surface to frictionally seat in a corresponding cylindrical recess positioned below the closure tab in the top closure wall, thereby closing the apertures in the bottom of the cylindrical recess and sealing against leakage of the contents from the container on which the closure cap is seated.